Regenerative braking - is it worth it?

W9GFO

Regenerative braking seems to be a desirable feature in robot drive controllers. There has been discussion concerning this and some doubt has been cast as to whether the regenerative drives are really effective.

I am curious to know if there has been any experiments testing a regenerative controller in a mobile robot against a standard controller to determine the difference.

It seems to me that very few robots would be operated in such a manner as to benefit from regenerative braking. I'm currently working on a large robot that will weigh in at more than 200 lbs. I anticipate that hard braking will occur very infrequently, as in having to stop sooner than planned. Generally I intend the robot to slow smoothly to a stop and accelerate smoothly. It won't be traveling down long grades either, I imagine most robots don't.

Any thought?

Rich H

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The Simple Servo Tester, a kit from Gadget Gangster.

mikediv

W9GFO I did a little deal using a small gas powered quad as the base the system used regenerative braking and it works quite well but as you pointed out its really only to matter in heavy systems 200Lb would qualify in small
house robots if you will I see no benefit unless the robot descends stairs or walls or something.. One of the things worth noting is the DC motors generate quite a bit of back power I was very surprised there was so much we actually have it dumping back into the batteries to help with longer life it works so well we do not have any mechanical braking on the machine at all expect for parking brake

erco

See also
http://forums.parallax.com/showthread.php?p=905079

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·"If you build it, they will come."

kwinn

In 2 words, "it depends".

Regenerative braking charges the battery whenever the robot is decelerating, so if the speed changes often (or travels up and down slopes) then it can make a substantial difference in the run time between charges.

On the other hand, if the robot runs at close to constant speed on flat surfaces most of the time regenerative braking may not make enough of a difference to justify the extra cost and circuit complexity.

W9GFO

What I was hoping for was some real word data. Such as "Since we switched our robot fleet to brand X controllers with regenerative braking we have been able to run our robots for 9% longer between charges".

Rich H

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The Simple Servo Tester, a kit from Gadget Gangster.

John R.

W9GFO said...
What I was hoping for was some real word data. Such as "Since we switched our robot fleet to brand X controllers with regenerative braking we have been able to run our robots for 9% longer between charges".

Rich H

Um, this may be the wrong spot to be looking for folks with "robot fleets".· I'n not sure where would be a better place, and there is nothing wrong (actually an intersting question) with posting here, but I'm thinking most of us don't have a "fleet" of robots, much·less in a position to compare regenerative vs standard control systems.

Just sayin'....

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John R.
Click here to see my Nomad Build Log

W9GFO

Right. As far as I know there aren't any regular members here with such a fleet. I guess I wasn't clear, I'll rephrase;

What I was hoping for was if someone knew of any real word data. Such as "Since we switched our robot fleet to brand X controllers with regenerative braking we have been able to run our robots for 9% longer between charges".

The theory behind regenerative braking is good and sound but all the evidence of it's true value in robot applications is anecdotal. It seems that the advantages are lauded but not quantified. Just wanting to know if anyone here knows of any hard data.

Rich H

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The Simple Servo Tester, a kit from Gadget Gangster.